Calculator



April 22, w41- R. L slFRx-r CALCULATOR Filed Aug. 4. les@ 2 Sheets-Sheetl joerfl. SP/ffii,

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2 Sheets-Sheet 2 R. L.. SIFRIT April 22, 1941.

GALCULATGR Filed Aug. 4, 1939 Patented Apr. 22, 1941 UNITED STATESPATENT OFFICE 4 Claims.

This invention relates to a new and useful device for calculating ordetermining the day when a menstrual period will begin, and the dayfertility will begin and the day fertility will end with respect to saidmenstrual period, for a given menstrual cycle and where the day theprevious menstrual period began is known.

The primary object of the present invention is to provide a calculatorof the above kind by means of which the dates mentioned above may berapidly and accurately ascertained in a simple and convenient manner.

Another object of the present invention is to provide a calculator ofthe above kind which is simple in construction, convenient to use, andeconomical to manufacture.

The present invention consists in the novel form, combination andarrangement of parts hereinafter more fully described, shown in theaccompanying drawings and claimed.

In the drawings:

Figure 1 is an elevational view of a calculator constructed inaccordance with the present invention.

Figure 2 is a longitudinal sectional view thereof taken on line 2 2 ofFigure 1.

Figure 3 is an elevational View of the inner cylinder.

Figure 4 is a transverse section on line 4-4 of Figure 1; and

Figure 5 is an enlarged fragmentary section on line 5--5 of Figure 1.

Referring in detail to the drawings, the present calculator comprisestwo concentrcally arranged cylinders and a sliding band or sleeve, theouter cylinder 5 being provided with three parallel lon.

gitudinal slots 6, l and 8 extending nearly from end to end thereof, andhaving a further short slot 9 at one end of the same. Also, arrangedlongitudinally upon the outer cylinder 5 adjacent the slot 6 are aseries of numbers I0 running from l to 31 and indicating the days of themonth.

The inner cylinder I I has a narrow end portion which extends beyond theadjacent end of the outer cylinder 5 and is enlarged and roughened orcorrugated as at I2 to facilitate turning of the inner cylinder II withrespect to the outer cylinder 5. At this end, the inner cylinder II isprovided with peripherally or circumferentially arranged notations I3 ofthe months of the year, any single one or group of which may be exposedthrough the slot 9 of the outer cylinder 5 by relatively rotating saidcylinders until the selected notation or group of notations I3 isregistered with said slot S as shown in Figure l. The inner cylinder IIis also provided upon its concealed major portion with a circumferentialseries of longitudinal rows of spaces I4, certain rows of spaces beingaligned with a month notation or group of month notations I3 of saidinner cylinder I I as shown clearly in Figure 3. These rows of spaces`I4 are adapted to receive, in predetermined relation, numeralsindicating days of the month. As these members will vary according tothe particular menstrual cycle for which the calculator is adapted, theyare not shown, although they can be readily determined and supplied.Suitable means may be provided for restraining the cylinders 5 and IIagainst relative rotation when the proper month notation or group ofmonth notations I3 has been alined with and exposed through the slot 9,said means being illustrated as a spring-pin catch I5 carried by an endof the outer cylinder 5 and having its pin extending inwardly andadapted to enter any one oi a circumferential series of openingsprovided in the adjacent end of the inner cylinder II as indicated atit. As the specic structure or nature of this means is not a part of thepresent invention per se, illustration thereof more in detail is deemedunnecessary.

The sliding band or sleeve I'l its snugly over the outer cylinder 5 soas to be manually movable longitudinally of the latter, and this band orsleeve is provided With four circumferentially arranged openings I8, I9,28 and 2l. The arrangement is such that when a month notation or groupof month notations I3 is alined with the slot 9, the numerals in threealternate ones of the rows of spaces I4 are exposed through the slots 6,'I and 8 of the outer cylinder 5. Also, when the sleeve Il is shiftedlongitudinally of the outer cylinder 5 so that one of the days of themonth indicating numerals IQ is registered with the opening I3 of saidband or sleeve Il, a numeral in one space of each of the rows I4 exposedthrough the slots 6, 'I and 8 will be respectively exposed through theopenings E9, 2?) and 2| of said band or sleeve I'I. With the properarrangement of numerals in the rows of spaces I4, the numeral exposedthrough the opening I 9 will indicate the day of the month when the nextmenstrual period will begin, the date of beginning of the previousmenstrual period being indicated by the month notation exposed throughthe slot 9 and the day of the month numeral exposed through the slot I3.Atthe same time, the numeral exposed through the opening 20 willindicate the day when fertility will begin with respect to the menstrualperiod whose date of beginning is indicated by the numeral exposedthrough the opening I9, and the numeral exposed through the opening ZIwill indicate the day when fertility will end with respect to the lattermenstrual period. In other words, assuming that the day when the lastmenstrual period began was March 14 as indicated by the notationsexposed through the slots 9 and I8 as shown in Figure l, the numeralsexposed through the openings I9, 20 and 2| of the sleeve Il willrespectively indicate the day when the next menstrual period will begin,the day when fertility will begin with respect to this next menstrualperiod, and the day when fertility will end with respect to such nextmenstrual period. With respect to any particular calculator, the dateswill of course only apply to one given menstrual cycle, which cycle mayvary from 26 to 3l days.

In order to releasably retain the sleeve or band l'I in any position ofadjustment longitudinally of the cylinder 5 wherein a numeral ID Aisexposed through its opening I8, said band or sleeve I'I may be providedwith a spring-pin catch 22 similar to that indicated at I5 and havingits pin passing inwardly through the sleeve I'I and arranged to enter adesired one of the longitudilnal series of openings 23 provided in theouter cylinder 5, one beneath each of the numerals Ill. These springcatches are preferably employed so that the device need not be carefullyhandled in order to prevent accidental displacement of the cylinderswhen they are set relative to each other or accidental displacement ofthe sleeve il longitudinally of the outer cylinder 5 when it has beenset in a predetermined position longitudinally of said cylinder 5.

In view of `the above, it will be seen that the present device providesfor showing the date of beginning of the next menstrual period and thedate of beginning and 'the date of ending of ferltility with respect tosaid period when the date of beginning of the previous menstrual periodis known, the respective first-mentioned dates being shown through theopenings I9, 20 and 2| of the sleeve II when said sleeve has beenpositioned so that the numeral i exposed -through Ithe opening Iii ofsleeve Il indicates the day of the month vwhen the previous menstrualperiod began, and when the outer cylinder has been adjusted relative `tothe inner cylinder I l so that the notation ES exposed through the slot9 indicates the month in which said previous menstrual period began. Itwill be understood :that the device illustrated in the drawings 'anddescribed herein is merely shown lby way of example of a form of myinvention that I consider to be desirable. Therefore, I do not confinemyself to the precise details shown and described. It is noted that themonth notations i3 are scientifically arranged and grouped both as 4tothe number of days contained in each month andthe number of Idays in thesucceeding month. By rst providing January, then February, then groupingMarchf May, August and October, then grouping ApriL J une, September andNovember, and finally grouping July and December, only rows I4 need beprovided with numerals.

What I claim as new is:

l. A menstrual and fertility calculator comprising an outer cylinderhaving three longitudinal slots therein extending the greater part ofthe length thereof, said outer cylinder also` having a short slot in oneend of the same and provid-ed with a longitudinal series of numeralsthereon opposite said slot indicating the days of a month, an innercylinder having a circumferential series of notations on one end thereofindi- -cating the months of the year and adapted to be selectivelyexposed through said short slot of the outer cylinder upon relativerotation of the cylinders, said inner cylinder also having acircumferential series of longitudinal rows of spaces adapted to receivenumerals indicating days of months, alternate rows being arranged forexposure through the longitudinal slots of the outer cylinder, `and asleeve tted over and longitudinally slidable on the outer cylinder andprovided with four circumfererrt-ally arranged openings adapted to berespectively registered with a numeral of said longitudinal series ofnumerals and a numeral of the respective rows of spaces exposed -throughthe three longitudinal slots of the outer cylinder, whereby, when saidsleeve and outer cylinder `are positioned to respectively reveal throughsaid short slot and an Iopening of the sleeve the month and day of saidmonth indicating the beginning of a given menstrual period, the numeralsexposed through the remaining openings of the sleeve and of the rowsexposed `through said longitudinal slots of Vthe outer cylinder willindicate respectively the day of 4beginning of the next menstrualperiod, the day of beginning of fertility with respect to the latterperiod, and the day of ending of fertility with respect to the latterperiod.

2. A menstrual and fertility calculator cornprising an outer cylinderhaving three longitudina'l slots therein extending the greater part ofthe length thereof, said outer cylinder =also having a short slot in oneend of the same and provided with a longitudinal series of numeralsthereon opposite said slot indicating the days of a month, an innercylinder having a circumferential series of notations on one end thereofindicating the months of the year and 'adapted to be selectively exposedthrough said short sloi'J of the outer cylinder upon relative rotation`of the cylinders, said inner cylinder also having a circumferentialseries of longitudinal rows of spaces adapted to receive numeralsindicating days of months, alternate rows being arranged for exposurethrough the longitudinal slots of the outer cylinder, a sleeve fittedover and longitudinally slidable on the outer cylinder and provided withfour circumferentially arranged openings adapted to =be respectivelyregistered with a numeral of said longitudinal series of numerals and anumeral of the respective rows of spaces exposed through the threelongitudinal slots of the outer cylinder, whereby, when said sleeve andouter cylinder are positioned to respectively reveal through said shortslot and an opening of the sleeve the month and day of said monthindicating the beginning of a given menstrual period, the numeralsexposed through the remaining openings of the sleeve and of the rowsexposed through said longitudinal slots of the outer cylinder willindicate respectively the day of -beginning of the next menstrualperiod, the day of beginning of fertility with respect to the latterperiod, and the day of ending of fertility with respect to the latterperiod, said inner cylinder having an end portion exposed beyond one endof the outer cylinder and enlarged and roughened t-o facilitate turningof said inner cylinder.

3. A menstrual and fertility calculator compris- `lng an outer cylinderhaving three longitudinal slots therein extending the greater part ofthe length thereof, said outer cylinder also having a short slot in oneend of the same and provided with a longitudinal series of numeralsthereon opposite said slot indicating the days of a month, an innercylinder having a circumferential series of notations on one end thereofindicating the months of the year and adapted to be selectively exposedthrough said short slot of the outer cylinder upon relative rotation ofthe cylinders, said inner cylinder also having a circumferential seriesof longitudinal rows of spaces adapted to receive numerals indicatingdays of months, alternate rows being arranged for exposure through thelongitudinal slots of the outer cylinder, a sleeve fitted over andlongitudinally slidable on the outer cylinder and provided with fourcircumferentially arranged openings adapted to be respectivelyregistered with a numeral of said 1ongitudinal series of numerals and anumeral of the respective rows of spaces exposed through the threelongitudinal slots of the outer cylinder, whereby, when said sleeve andouter cylinder are positioned to respectively reveal through said shortslot and opening of the sleeve the month and day of said month of agiven menstrual period, the numerals exposed through the remainingopenings of the sleeve and of the rows exposed through said longitudinalslots of the outer cylinder will indicate respectively the day ofbeginning of the next menstrual period, the day of beginning offertility with respect to the latter period, and the day of ending offertility with respect to the latter period, and means to releasablyretain the sleeve in different positions of adjustment longitudinally ofthe outer cylinder.

4. A menstrual and fertility calculator comprising an outer cylinderhaving three longitudinal slots therein extending the greater part ofthe length thereof, said outer cylinder also having a short slot in oneend of the same and provided Withua longitudinal series of numeralsthereon opposite said slot indicating the days of a month, an innercylinder having a circumferential series of notations on one end thereofindicating the months of the year and adapted to be selectively exposedthrough said short slot of the outer cylinder upon relative rotation ofthe cylinders, said inner cylinder also having a circumferential seriesof longitudinal rows of spaces adapted to receive numerals indicatingdays of months, alternate rows being arranged for exposure through thelongitudinal slots of the outer cylinder, a sleeve fitted over andlongitudinally slidable on the outer cylinder and provided with fourcircumferentially arranged openings adapted to be respectivelyregistered with a numeral of said longitudinal series of numerals and anumeral of the respective rows of spaces exposed through the threelongitudinal slots of the outer cylinder, whereby, when said sleeve andouter cylinder are positioned to respectively reveal through said shortslot and an opening of the sleeve the month and day of said month of agiven menstrual period, the numerals exposed through the remainingopenings of the sleeve and of the rows exposed through said longitudinalslots of the outer cylinder will indicate respectively the day ofbeginning of the next menstrual period, the day of beginning offertility with respect to the latter period, and the day of ending offertility with respect to the latter period, and means to releasablyretain the outer cylinder against rotation relative to the innercylinder in different positions of relative rotary adjustment of saidcylinders.

ROBERT L, SIFRIT.

